A species of cold water plankton (C. finmarchicus) in the North Atlantic, which is a vital food source for fish such as cod and hake, is in decline as the oceans warm. This will put pressure on the fisheries that rely on abundant supplies of these fish.
Scientists know that warm water species are expanding their ranges as warming occurs. What is unknown is whether cold water species will gradually adapt to new temperatures so they can withstand warming seas and not continually contract their ranges. From the results of research, the answer is no.
The impact of ocean warming was not confined to the North Atlantic region. Ocean warming is occurring globally and so these findings are likely to apply to other areas around the world including southern hemisphere locations such as Australia, South Africa and South America that support important fisheries dependent on plankton.